This invention generally relates to convoluted sleeving having heat-reflective, insulative and protective properties. More particularly, the invention relates to a convoluted assembly including a convoluted polymeric tubing to which is conformingly adhered a laminate of reflective foil with insulating fabric. The convoluted heat-reflective, protective sleeving assembly exhibits good lateral flexibility, typically being substantially the same as the lateral flexibility of the convoluted polymeric tubing alone. Manufacturing is preferably accomplished by wrapping the laminate of foil and fabric over the external convoluted tubing profile of the convoluted polymeric while simultaneously directing portions of the laminate into the grooves of the external convolute tubing profile such that the laminate closely engages both the crests and the grooves of the external convoluted tubing profile in order to accomplish the conforming overlying structure.
In the past, various approaches have been taken in order to provide protective tubular coverings for conduits, cables, lines, wire harnesses and other components needing shielding from either the elements or other components or equipment. Usually, these components are found under the hood or elsewhere in vehicles, particularly automobiles and trucks. Often, an important property required of these types of protective tubings is to provide shielding from heat as well as protection from abrasion and the like. Typical automotive uses are in connection with fuel, brake, hydraulic, coolant and air conditioning lines and wire harnesses. These components may be made of diverse materials such as metals, polymers, plastics or rubbers.
An exemplary existing tubing or sleeving product is an aluminized fiberglass fabric shaped into a tube and sewn along a longitudinal seam. Products of this type can offer generally adequate reflective thermal protection, but they are deficient in providing flexibility needed in order to unobtrusively follow bends and curves in the line or other component being protected by the tubing. Some applications require a longitudinally slit tubing; however, products such as sewn aluminized fiberglass fabric cannot be slit without unraveling. This lack of flexibility and inability to be slit that is characteristic of these types of prior approaches can be accommodated somewhat by utilizing tubings that have diameters which are well oversized from diameters which would otherwise be required to accommodate the size of the line or the like being protected. When sewn aluminized fiberglass fabric tubings are used, there is a tendency for the stitching at the ends of the seams to rip back, especially during extended and rough usage.
Another existing approach in providing sleeving products for these types of applications is the use of fiberglass braid. Fiberglass braid offers elevated temperature protection and good flexibility; however, the openness of the braided yarns allows thermal leakage, the ends of the braided yarn are prone to fraying, and this type of component cannot be longitudinally slit for those applications where the ends of the line or the like which is to be protected are obstructed and do not allow for sliding insertion onto the line or the like.
In accordance with the present invention, a sleeving is provided which has superior flexibility while still offering excellent reflective and thermal protection and while being of a construction that advantageously accommodates longitudinal slitting when needed. In addition, its construction enhances heat dissipation when in use.